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Aproperty title search firm is contemplating using online software to increase its search productivity. currently an average of 40 minutes is needed to do a title search. the researcher cost is $2 per minute. clients are charged a fee of $400. company a's software would reduce the average search time by 10 minutes, at a cost of $3.50 per search. company b's software would reduce the average search time by 12 minutes at a cost of $3.60 per search. which option would have the higher productivity in terms of revenue per dollar of input?